The present invention relates to an arrangement for resiliently absorbing forces, particularly for intermediate buffer couplings for rail vehicles.
Arrangement of the above-mentioned general type are known in the art. A known arrangement has a housing which is closed at its one end, and a resilient support of element accommodated in the housing. The resilient support cooperates in series with a friction device in the region of an open end of the housing. An opening of the open end of the housing has a diameter which is smaller than the inner diameter of a portion of the housing, in which the resilient support is located.
Spring arrangements provided in conventional draw and buffer arrangements must be constructed so as to perform the stroke in correspondence with especially high energy absorption which is required in connection with increasing weight of the vehicles and careful treatment of transported loads.
One of the known arrangements is disclosed in the German Auslegeschrift No. 1,455,238. The friction device of this arrangement comprises a substantially central wedge-formed member with surrounding friction shoes. The housing of the arrangement is provided at its open end with projections which reduce the cross-section of the opening of the housing. Further projections provided on the wedge-formed member cooperate with the above-mentioned projections of the housing so as to limit outward displacement. When percussive force acts upon the arrangement, the central wedge-formed member displaces into the interior of the housing. This force is split into two components or inclined surfaces of the wedge-formed member and inclined surfaces of the friction shoes, which surfaces form wedge pairs. One of the force components presses the friction shoes inwardly into the housing, whereas the other force component presses the friction shoes outwardly toward strong frictional engagement with respective inner surfaces in the region of the open end of the housing. The cylindrical resilient element counteracts the inward displacement of the friction shoe, with interposition of a plate. The resilient element has a stiffness codetermined for the energy absorption of the friction device. The resilient element in the known construction is composed of interconnected disc springs of rubber or similar elastomeric material, which allows to support the friction device and to return it to its starting position only to the limited extent. At the same time, it is known from experience that such springs have a service life which is smaller than that of the vehicle.